Glycosyl transferases isolated by affinity chromatography on agarose derivatized with nucleotide diphosphates, glycosyl diphosphates and glycosides will be used to elongate the glycosyl residues of glycosyl-agarose adsorbants. The modified adsorbant will then be used to isolate additional transferases resulting in a system for the synthesis of naturally occuring oligosaccharides attached to agarose. A labile linkage for the attachment of glycosides to agarose is proposed to allow the isolation of oligosaccharide formed in this way and their testing biological systems.